fix special attribute name on IE.

[liudongmiao]

This patch should fix Polymer/polymer#332
and Polymer/polymer#372

The list of pissible wrong attributes can be retrieved by following codes:

    var blacklist = [];
    Object.keys(HTMLElement.prototype).forEach(function (item) {
        try {
            HTMLElement.prototype[item];
        } catch (e) {
            console.log(item + ": " + e.name + ", " + e.message);
            blacklist.push(item);
        }
    });
    blacklist.sort();
    document.write("<h3>blacklist</h3>" + blacklist.join("<br/>"));

Here is a single web page http://jsbin.com/gofay/1

[ebidel]

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